cons_linking.c File Reference

Detailed Description

constraint handler for linking constraints

Author

Stefan Heinz

Jens Schulz

The constraints handler stores linking constraints between an integer variable and an array of binary variables. Such a linking constraint has the form:

intvar = sum_{i=1}^n {vals[i] * binvars[i]}

with the additional side condition that exactly one binary variable has to be one (set partitioning condition).

This constraint can be created only with the integer variable. In this case the binary variables are only created on demand. That is, whenever someone asks for the binary variables. Therefore, such constraints can be used to get a "binary representation" of the domain of the integer variable which will be dynamically created.

Definition in file cons_linking.c.

#include <assert.h>
#include <string.h>
#include <ctype.h>
#include "scip/cons_linear.h"
#include "scip/cons_linking.h"
#include "scip/cons_setppc.h"

Go to the source code of this file.

Macros
#define	CONSHDLR_NAME   "linking"
#define	CONSHDLR_DESC   "linking constraint x = sum_{i=1}^{n} c_i*y_i, y1+...+yn = 1, x integer, y's binary"
#define	EVENTHDLR_NAME   "linking"
#define	EVENTHDLR_DESC   "event handler for linking constraints"
#define	CONSHDLR_SEPAPRIORITY   750000
#define	CONSHDLR_ENFOPRIORITY   -2050000
#define	CONSHDLR_CHECKPRIORITY   -750000
#define	CONSHDLR_SEPAFREQ   1
#define	CONSHDLR_PROPFREQ   1
#define	CONSHDLR_EAGERFREQ   100
#define	CONSHDLR_MAXPREROUNDS   -1
#define	CONSHDLR_DELAYSEPA   FALSE
#define	CONSHDLR_DELAYPROP   FALSE
#define	CONSHDLR_DELAYPRESOL   FALSE
#define	CONSHDLR_NEEDSCONS   TRUE
#define	CONSHDLR_PROP_TIMING   SCIP_PROPTIMING_BEFORELP
#define	HASHSIZE_BINVARSCONS   131101
#define	DEFAULT_LINEARIZE   FALSE

Functions
static void *	getHashmapKey (SCIP_VAR *var)
static void	consdataSort (SCIP_CONSDATA *consdata)
static SCIP_RETCODE	lockRounding (SCIP *scip, SCIP_CONS *cons, SCIP_VAR **binvars, int nbinvars)
static SCIP_RETCODE	conshdlrdataCreate (SCIP *scip, SCIP_CONSHDLRDATA **conshdlrdata, SCIP_EVENTHDLR *eventhdlr)
static SCIP_RETCODE	conshdlrdataFree (SCIP *scip, SCIP_CONSHDLRDATA **conshdlrdata)
static SCIP_RETCODE	consdataPrint (SCIP *scip, SCIP_CONSDATA *consdata, FILE *file)
static SCIP_RETCODE	catchEvent (SCIP *scip, SCIP_CONSDATA *consdata, SCIP_EVENTHDLR *eventhdlr, int pos)
static SCIP_RETCODE	dropEvent (SCIP *scip, SCIP_CONSDATA *consdata, SCIP_EVENTHDLR *eventhdlr, int pos)
static SCIP_RETCODE	catchAllEvents (SCIP *scip, SCIP_CONSDATA *consdata, SCIP_EVENTHDLR *eventhdlr)
static SCIP_RETCODE	dropAllEvents (SCIP *scip, SCIP_CONSDATA *consdata, SCIP_EVENTHDLR *eventhdlr)
static SCIP_RETCODE	consdataLinearize (SCIP *scip, SCIP_CONS *cons, SCIP_CONSDATA *consdata)
static SCIP_RETCODE	consdataCreateBinvars (SCIP *scip, SCIP_CONS *cons, SCIP_CONSDATA *consdata, SCIP_EVENTHDLR *eventhdlr, SCIP_Bool linearize)
static SCIP_RETCODE	consdataCreate (SCIP *scip, SCIP_EVENTHDLR *eventhdlr, SCIP_CONSDATA **consdata, SCIP_VAR *intvar, SCIP_VAR **binvars, int *vals, int nbinvars)
static SCIP_RETCODE	consdataFree (SCIP *scip, SCIP_CONSDATA **consdata)
static SCIP_RETCODE	analyzeConflict (SCIP *scip, SCIP_CONS *cons, SCIP_VAR *intvar, SCIP_VAR *binvar, SCIP_Bool lbintvar, SCIP_Bool ubintvar)
static SCIP_RETCODE	consFixInteger (SCIP *scip, SCIP_CONS *cons, int pos, SCIP_Bool *cutoff)
static SCIP_RETCODE	processIntegerBoundChg (SCIP *scip, SCIP_CONS *cons, SCIP_Bool *cutoff, int *nchgbds, SCIP_Bool *mustcheck)
static SCIP_RETCODE	delCoefPos (SCIP *scip, SCIP_EVENTHDLR *eventhdlr, SCIP_CONS *cons, int pos)
static SCIP_RETCODE	removeFixedBinvars (SCIP *scip, SCIP_EVENTHDLR *eventhdlr, SCIP_CONS *cons)
static SCIP_RETCODE	tightenedIntvar (SCIP *scip, SCIP_CONS *cons, SCIP_CONSDATA *consdata, SCIP_Bool *cutoff, int *nchgbds)
static SCIP_RETCODE	processBinvarFixings (SCIP *scip, SCIP_CONS *cons, SCIP_Bool *cutoff, int *nchgbds, SCIP_Bool *addcut, SCIP_Bool *mustcheck)
static SCIP_Bool	checkCons (SCIP *scip, SCIP_CONS *cons, SCIP_SOL *sol)
static SCIP_RETCODE	createRows (SCIP *scip, SCIP_CONS *cons)
static SCIP_RETCODE	addCuts (SCIP *scip, SCIP_CONS *cons, SCIP_SOL *sol, SCIP_Bool *cutoff)
static SCIP_RETCODE	separateCons (SCIP *scip, SCIP_CONS *cons, SCIP_SOL *sol, SCIP_Bool *cutoff, SCIP_Bool *separated, int *nchgbds)
static SCIP_RETCODE	enforcePseudo (SCIP *scip, SCIP_CONS *cons, SCIP_Bool *cutoff, SCIP_Bool *infeasible, int *nchgbds, SCIP_Bool *solvelp)
static	SCIP_DECL_CONSHDLRCOPY (conshdlrCopyLinking)
static	SCIP_DECL_CONSFREE (consFreeLinking)
static	SCIP_DECL_CONSINITPRE (consInitpreLinking)
static	SCIP_DECL_CONSEXITSOL (consExitsolLinking)
static	SCIP_DECL_CONSDELETE (consDeleteLinking)
static	SCIP_DECL_CONSTRANS (consTransLinking)
static	SCIP_DECL_CONSINITLP (consInitlpLinking)
static	SCIP_DECL_CONSSEPALP (consSepalpLinking)
static	SCIP_DECL_CONSSEPASOL (consSepasolLinking)
static	SCIP_DECL_CONSENFOLP (consEnfolpLinking)
static	SCIP_DECL_CONSENFOPS (consEnfopsLinking)
static	SCIP_DECL_CONSCHECK (consCheckLinking)
static	SCIP_DECL_CONSPROP (consPropLinking)
static	SCIP_DECL_CONSPRESOL (consPresolLinking)
static	SCIP_DECL_CONSRESPROP (consRespropLinking)
static	SCIP_DECL_CONSLOCK (consLockLinking)
static	SCIP_DECL_CONSENABLE (consEnableLinking)
static	SCIP_DECL_CONSPRINT (consPrintLinking)
static	SCIP_DECL_CONSCOPY (consCopyLinking)
static	SCIP_DECL_CONSPARSE (consParseLinking)
static	SCIP_DECL_CONSGETVARS (consGetVarsLinking)
static	SCIP_DECL_CONSGETNVARS (consGetNVarsLinking)
static	SCIP_DECL_EVENTEXEC (eventExecBinvar)
SCIP_RETCODE	SCIPincludeConshdlrLinking (SCIP *scip)
SCIP_RETCODE	SCIPcreateConsLinking (SCIP *scip, SCIP_CONS **cons, const char *name, SCIP_VAR *intvar, SCIP_VAR **binvars, int *vals, int nbinvars, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
SCIP_RETCODE	SCIPcreateConsBasicLinking (SCIP *scip, SCIP_CONS **cons, const char *name, SCIP_VAR *intvar, SCIP_VAR **binvars, int *vals, int nbinvars)
SCIP_Bool	SCIPexistsConsLinking (SCIP *scip, SCIP_VAR *intvar)
SCIP_CONS *	SCIPgetConsLinking (SCIP *scip, SCIP_VAR *intvar)
SCIP_VAR *	SCIPgetIntvarLinking (SCIP *scip, SCIP_CONS *cons)
SCIP_RETCODE	SCIPgetBinvarsLinking (SCIP *scip, SCIP_CONS *cons, SCIP_VAR ***binvars, int *nbinvars)
int	SCIPgetNBinvarsLinking (SCIP *scip, SCIP_CONS *cons)
int *	SCIPgetValsLinking (SCIP *scip, SCIP_CONS *cons)

Macro Definition Documentation

#define CONSHDLR_NAME   "linking"

Definition at line 49 of file cons_linking.c.

Referenced by enforcePseudo(), processBinvarFixings(), processIntegerBoundChg(), SCIP_DECL_CONSCHECK(), SCIP_DECL_CONSCOPY(), SCIP_DECL_CONSDELETE(), SCIP_DECL_CONSENFOLP(), SCIP_DECL_CONSENFOPS(), SCIP_DECL_CONSFREE(), SCIP_DECL_CONSHDLRCOPY(), SCIP_DECL_CONSPRESOL(), SCIP_DECL_CONSPROP(), SCIP_DECL_CONSRESPROP(), SCIP_DECL_CONSSEPALP(), SCIP_DECL_CONSSEPASOL(), SCIP_DECL_CONSTRANS(), SCIPcreateConsLinking(), SCIPexistsConsLinking(), SCIPgetBinvarsLinking(), SCIPgetConsLinking(), SCIPgetIntvarLinking(), SCIPgetNBinvarsLinking(), SCIPgetValsLinking(), SCIPincludeConshdlrLinking(), and separateCons().

#define CONSHDLR_DESC   "linking constraint x = sum_{i=1}^{n} c_i*y_i, y1+...+yn = 1, x integer, y's binary"

Definition at line 50 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define EVENTHDLR_NAME   "linking"

Definition at line 52 of file cons_linking.c.

Referenced by SCIP_DECL_EVENTEXEC(), and SCIPincludeConshdlrLinking().

#define EVENTHDLR_DESC   "event handler for linking constraints"

Definition at line 53 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_SEPAPRIORITY   750000

priority of the constraint handler for separation

Definition at line 55 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_ENFOPRIORITY   -2050000

priority of the constraint handler for constraint enforcing

Definition at line 56 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_CHECKPRIORITY   -750000

priority of the constraint handler for checking feasibility

Definition at line 57 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_SEPAFREQ   1

frequency for separating cuts; zero means to separate only in the root node

Definition at line 58 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_PROPFREQ   1

frequency for propagating domains; zero means only preprocessing propagation

Definition at line 59 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_EAGERFREQ   100

frequency for using all instead of only the useful constraints in separation, propagation and enforcement, -1 for no eager evaluations, 0 for first only

Definition at line 60 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_MAXPREROUNDS   -1

maximal number of presolving rounds the constraint handler participates in (-1: no limit)

Definition at line 61 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_DELAYSEPA   FALSE

should separation method be delayed, if other separators found cuts?

Definition at line 62 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_DELAYPROP   FALSE

should propagation method be delayed, if other propagators found reductions?

Definition at line 63 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_DELAYPRESOL   FALSE

should presolving method be delayed, if other presolvers found reductions?

Definition at line 64 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_NEEDSCONS   TRUE

should the constraint handler be skipped, if no constraints are available?

Definition at line 65 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define CONSHDLR_PROP_TIMING   SCIP_PROPTIMING_BEFORELP

Definition at line 67 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

#define HASHSIZE_BINVARSCONS   131101

minimal size of hash table in linking constraint handler

Definition at line 70 of file cons_linking.c.

Referenced by SCIPcreateConsLinking().

#define DEFAULT_LINEARIZE   FALSE

should the linking constraint be linearize after the binary variable are created

Definition at line 71 of file cons_linking.c.

Referenced by SCIPincludeConshdlrLinking().

Function Documentation

static void* getHashmapKey ( SCIP_VAR *  var )

static

returns for a given integer variable the corresponding hash map key

Parameters

var	variable to get the hash map key for

Definition at line 109 of file cons_linking.c.

References SCIPvarGetIndex().

Referenced by SCIP_DECL_CONSDELETE(), SCIP_DECL_CONSTRANS(), SCIPcreateConsLinking(), SCIPexistsConsLinking(), and SCIPgetConsLinking().

static void consdataSort ( SCIP_CONSDATA *  consdata )

static

Parameters

consdata

linking constraint data

Definition at line 119 of file cons_linking.c.

References SCIPsortIntPtr(), and TRUE.

Referenced by processBinvarFixings(), and processIntegerBoundChg().

static SCIP_RETCODE lockRounding ( SCIP *  scip, SCIP_CONS *  cons, SCIP_VAR **  binvars, int  nbinvars  )

static

installs rounding locks for the binary variables in the given linking constraint

Parameters

scip	SCIP data structure
cons	linking constraint
binvars	binary variables
nbinvars	number of binary variables

Definition at line 135 of file cons_linking.c.

References SCIP_CALL, SCIP_OKAY, SCIPlockVarCons(), and TRUE.

Referenced by consdataCreateBinvars().

static SCIP_RETCODE conshdlrdataCreate ( SCIP *  scip, SCIP_CONSHDLRDATA **  conshdlrdata, SCIP_EVENTHDLR *  eventhdlr  )

static

creates constraint handler data for the linking constraint handler

Parameters

scip	SCIP data structure
conshdlrdata	pointer to store the constraint handler data
eventhdlr	event handler

Definition at line 154 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_OKAY, and SCIPallocMemory.

Referenced by SCIPincludeConshdlrLinking().

static SCIP_RETCODE conshdlrdataFree ( SCIP *  scip, SCIP_CONSHDLRDATA **  conshdlrdata  )

static

frees constraint handler data for linking constraint handler

Parameters

scip	SCIP data structure
conshdlrdata	pointer to the constraint handler data

Definition at line 177 of file cons_linking.c.

References NULL, SCIP_OKAY, SCIPfreeMemory, and SCIPhashmapFree().

Referenced by SCIP_DECL_CONSFREE().

static SCIP_RETCODE consdataPrint ( SCIP *  scip, SCIP_CONSDATA *  consdata, FILE *  file  )

static

prints linking constraint to file stream

Parameters

scip	SCIP data structure
consdata	linking constraint data
file	output file (or NULL for standard output)

Definition at line 197 of file cons_linking.c.

References FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPallocBufferArray, SCIPfreeBufferArray, SCIPinfoMessage(), SCIPwriteVarName(), and SCIPwriteVarsLinearsum().

Referenced by SCIP_DECL_CONSPRINT().

static SCIP_RETCODE catchEvent ( SCIP *  scip, SCIP_CONSDATA *  consdata, SCIP_EVENTHDLR *  eventhdlr, int  pos  )

static

catches events for variable at given position

Parameters

scip	SCIP data structure
consdata	linking constraint data
eventhdlr	event handler to call for the event processing
pos	array position of variable to catch bound change events for

Definition at line 251 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_EVENTTYPE_BOUNDCHANGED, SCIP_OKAY, SCIPcatchVarEvent(), SCIPisEQ(), SCIPvarGetLbLocal(), and SCIPvarGetUbLocal().

Referenced by catchAllEvents().

static SCIP_RETCODE dropEvent ( SCIP *  scip, SCIP_CONSDATA *  consdata, SCIP_EVENTHDLR *  eventhdlr, int  pos  )

static

drops events for variable at given position

Parameters

scip	SCIP data structure
consdata	linking constraint data
eventhdlr	event handler to call for the event processing
pos	array position of variable to catch bound change events for

Definition at line 283 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_EVENTTYPE_BOUNDCHANGED, SCIP_OKAY, SCIPdropVarEvent(), SCIPisEQ(), SCIPvarGetLbLocal(), and SCIPvarGetUbLocal().

Referenced by delCoefPos(), and dropAllEvents().

static SCIP_RETCODE catchAllEvents ( SCIP *  scip, SCIP_CONSDATA *  consdata, SCIP_EVENTHDLR *  eventhdlr  )

static

catches bound change events for all variables in transformed linking constraint

Parameters

scip	SCIP data structure
consdata	linking constraint data
eventhdlr	event handler to call for the event processing

Definition at line 314 of file cons_linking.c.

References catchEvent(), NULL, SCIP_CALL, and SCIP_OKAY.

Referenced by consdataCreate(), and consdataCreateBinvars().

static SCIP_RETCODE dropAllEvents ( SCIP *  scip, SCIP_CONSDATA *  consdata, SCIP_EVENTHDLR *  eventhdlr  )

static

drops bound change events for all variables in transformed linking constraint

Parameters

scip	SCIP data structure
consdata	linking constraint data
eventhdlr	event handler to call for the event processing

Definition at line 338 of file cons_linking.c.

References dropEvent(), NULL, SCIP_CALL, and SCIP_OKAY.

Referenced by SCIP_DECL_CONSDELETE().

static SCIP_RETCODE consdataLinearize ( SCIP *  scip, SCIP_CONS *  cons, SCIP_CONSDATA *  consdata  )

static

linearize the given linking constraint into a set partitioning constraint for the binary variables and a linear constraint for the linking between the integer variable and the binary variables

Parameters

scip	SCIP data structure
cons	linking constraint
consdata	linking constraint data

Definition at line 363 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPaddCoefLinear(), SCIPaddCons(), SCIPconsGetName(), SCIPconsIsChecked(), SCIPconsIsDynamic(), SCIPconsIsEnforced(), SCIPconsIsInitial(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsPropagated(), SCIPconsIsRemovable(), SCIPconsIsSeparated(), SCIPconsIsStickingAtNode(), SCIPcreateConsLinear(), SCIPcreateConsSetpart(), SCIPdebugMessage, and SCIPreleaseCons().

Referenced by consdataCreateBinvars(), SCIP_DECL_CONSENABLE(), and SCIP_DECL_CONSINITPRE().

static SCIP_RETCODE consdataCreateBinvars ( SCIP *  scip, SCIP_CONS *  cons, SCIP_CONSDATA *  consdata, SCIP_EVENTHDLR *  eventhdlr, SCIP_Bool  linearize  )

static

creates the binary variables

Parameters

scip	SCIP data structure
cons	linking constraint
consdata	linking constraint data
eventhdlr	event handler for bound change events on binary variables
linearize	should the linking constraint be linearized

Definition at line 402 of file cons_linking.c.

References catchAllEvents(), consdataLinearize(), FALSE, lockRounding(), NULL, SCIP_CALL, SCIP_MAXSTRLEN, SCIP_OKAY, SCIP_VARTYPE_BINARY, SCIPaddVar(), SCIPallocBlockMemoryArray, SCIPcreateVar(), SCIPdebugMessage, SCIPenableCons(), SCIPisTransformed(), SCIPsnprintf(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetUbGlobal(), and TRUE.

Referenced by SCIPgetBinvarsLinking().

static SCIP_RETCODE consdataCreate ( SCIP *  scip, SCIP_EVENTHDLR *  eventhdlr, SCIP_CONSDATA **  consdata, SCIP_VAR *  intvar, SCIP_VAR **  binvars, int *  vals, int  nbinvars  )

static

creates consdata

Parameters

scip	SCIP data structure
eventhdlr	event handler to call for the event processing
consdata	pointer to constraint data
intvar	integer variable which is linked
binvars	binary variables
vals	coefficients of the binary variables
nbinvars	number of binary starting variables

Definition at line 497 of file cons_linking.c.

References catchAllEvents(), FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIP_VARTYPE_CONTINUOUS, SCIPallocBlockMemory, SCIPcaptureVar(), SCIPduplicateBlockMemoryArray, SCIPgetTransformedVar(), SCIPgetTransformedVars(), SCIPisTransformed(), SCIPmarkDoNotMultaggrVar(), and SCIPvarGetType().

Referenced by SCIP_DECL_CONSTRANS(), and SCIPcreateConsLinking().

static SCIP_RETCODE consdataFree ( SCIP *  scip, SCIP_CONSDATA **  consdata  )

static

free consdata

Parameters

scip	SCIP data structure
consdata	pointer to consdata

Definition at line 577 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPfreeBlockMemory, SCIPfreeBlockMemoryArray, SCIPreleaseRow(), and SCIPreleaseVar().

Referenced by SCIP_DECL_CONSDELETE().

static SCIP_RETCODE analyzeConflict ( SCIP *  scip, SCIP_CONS *  cons, SCIP_VAR *  intvar, SCIP_VAR *  binvar, SCIP_Bool  lbintvar, SCIP_Bool  ubintvar  )

static

analyzes conflicting assignment on given constraint where reason comes from the integer variable lower or upper bound

Parameters

scip	SCIP data structure
cons	linking constraint to be processed
intvar	integer variable
binvar	binary variable is the reason
lbintvar	lower bound of integer variable is the reason
ubintvar	upper bound of integer variable is the reason

Definition at line 628 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIP_STAGE_SOLVING, SCIPaddConflictBinvar(), SCIPaddConflictLb(), SCIPaddConflictUb(), SCIPanalyzeConflictCons(), SCIPgetStage(), SCIPinitConflictAnalysis(), SCIPinProbing(), and SCIPisConflictAnalysisApplicable().

Referenced by consFixInteger(), and processIntegerBoundChg().

static SCIP_RETCODE consFixInteger ( SCIP *  scip, SCIP_CONS *  cons, int  pos, SCIP_Bool *  cutoff  )

static

fix integer variable to the value of the binary variable at pos

Parameters

scip	SCIP data structure
cons	linking constraint to be processed
pos	position of binary variable
cutoff	pointer to store TRUE, if the node can be cut off

Definition at line 671 of file cons_linking.c.

References analyzeConflict(), FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPconsGetData(), SCIPinferVarLbCons(), SCIPinferVarUbCons(), SCIPvarGetLbLocal(), SCIPvarGetUbLocal(), and TRUE.

Referenced by processBinvarFixings().

static SCIP_RETCODE processIntegerBoundChg ( SCIP *  scip, SCIP_CONS *  cons, SCIP_Bool *  cutoff, int *  nchgbds, SCIP_Bool *  mustcheck  )

static

checks constraint for violation from the local bound of the integer variable, applies fixings to the binary variables if possible

Parameters

scip	SCIP data structure
cons	linking constraint to be processed
cutoff	pointer to store TRUE, if the node can be cut off
nchgbds	pointer to store the number of changes (foxed) variable bounds
mustcheck	pointer to store whether this constraint must be checked for feasibility

Definition at line 728 of file cons_linking.c.

References analyzeConflict(), consdataSort(), CONSHDLR_NAME, FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIPaddCons(), SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconsGetName(), SCIPconshdlrGetName(), SCIPconsIsChecked(), SCIPconsIsDynamic(), SCIPconsIsEnforced(), SCIPconsIsInitial(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsPropagated(), SCIPconsIsRemovable(), SCIPconsIsSeparated(), SCIPconsIsStickingAtNode(), SCIPcreateConsSetpart(), SCIPdebugMessage, SCIPdelConsLocal(), SCIPgetDepth(), SCIPinferBinvarCons(), SCIPreleaseCons(), SCIPvarGetLbLocal(), SCIPvarGetName(), SCIPvarGetUbLocal(), and TRUE.

Referenced by enforcePseudo(), SCIP_DECL_CONSPRESOL(), SCIP_DECL_CONSPROP(), and separateCons().

static SCIP_RETCODE delCoefPos ( SCIP *  scip, SCIP_EVENTHDLR *  eventhdlr, SCIP_CONS *  cons, int  pos  )

static

deletes coefficient at given position from the binary variable array

Parameters

scip	SCIP data structure
eventhdlr	event handler to call for the event processing
cons	linking constraint
pos	position of coefficient to delete

Definition at line 919 of file cons_linking.c.

References dropEvent(), FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetData(), SCIPconsIsTransformed(), SCIPreleaseVar(), SCIPunlockVarCons(), SCIPvarIsTransformed(), and TRUE.

Referenced by removeFixedBinvars().

static SCIP_RETCODE removeFixedBinvars ( SCIP *  scip, SCIP_EVENTHDLR *  eventhdlr, SCIP_CONS *  cons  )

static

remove the trailing and leeading binary variable which are fixed to zero

Parameters

scip	SCIP data structure
eventhdlr	event handler to call for the event processing
cons	linking constraint

Definition at line 977 of file cons_linking.c.

References delCoefPos(), NULL, SCIP_CALL, SCIP_OKAY, SCIP_STAGE_PRESOLVING, SCIPconsGetData(), SCIPgetDepth(), SCIPgetStage(), SCIPinProbing(), SCIPinRepropagation(), and SCIPvarGetUbLocal().

Referenced by SCIP_DECL_CONSPRESOL().

static SCIP_RETCODE tightenedIntvar ( SCIP *  scip, SCIP_CONS *  cons, SCIP_CONSDATA *  consdata, SCIP_Bool *  cutoff, int *  nchgbds  )

static

tightened the integer variable due to binary variables which are fixed to zero

Parameters

scip	SCIP data structure
cons	linking constraint to be processed
consdata	linking constraint to be processed
cutoff	pointer to store TRUE, if the node can be cut off
nchgbds	pointer to store the number of changed variable bounds

Definition at line 1024 of file cons_linking.c.

References NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_STAGE_SOLVING, SCIPaddConflictBinvar(), SCIPaddConflictLb(), SCIPaddConflictUb(), SCIPanalyzeConflictCons(), SCIPdebugMessage, SCIPgetStage(), SCIPinferVarLbCons(), SCIPinferVarUbCons(), SCIPinitConflictAnalysis(), SCIPinProbing(), SCIPisConflictAnalysisApplicable(), SCIPvarGetLbLocal(), SCIPvarGetName(), SCIPvarGetUbLocal(), and TRUE.

Referenced by processBinvarFixings(), and SCIP_DECL_CONSPRESOL().

static SCIP_RETCODE processBinvarFixings ( SCIP *  scip, SCIP_CONS *  cons, SCIP_Bool *  cutoff, int *  nchgbds, SCIP_Bool *  addcut, SCIP_Bool *  mustcheck  )

static

checks constraint for violation only looking at the fixed binary variables, applies further fixings if possible

Parameters

scip	SCIP data structure
cons	linking constraint to be processed
cutoff	pointer to store TRUE, if the node can be cut off
nchgbds	pointer to store the number of changed variable bounds
addcut	pointer to store whether this constraint must be added as a cut
mustcheck	pointer to store whether this constraint must be checked for feasibility

Definition at line 1160 of file cons_linking.c.

References consdataSort(), consFixInteger(), CONSHDLR_NAME, FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_STAGE_SOLVING, SCIPaddConflictBinvar(), SCIPanalyzeConflictCons(), SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconsGetName(), SCIPconshdlrGetName(), SCIPconsIsModifiable(), SCIPdebugMessage, SCIPdelConsLocal(), SCIPgetStage(), SCIPinferBinvarCons(), SCIPinitConflictAnalysis(), SCIPinProbing(), SCIPisConflictAnalysisApplicable(), SCIPisFeasEQ(), SCIPisFeasZero(), SCIPisLT(), SCIPresetConsAge(), SCIPvarGetLbLocal(), SCIPvarGetName(), SCIPvarGetUbLocal(), SCIPvarIsBinary(), tightenedIntvar(), and TRUE.

Referenced by enforcePseudo(), and SCIP_DECL_CONSPROP().

static SCIP_Bool checkCons ( SCIP *  scip, SCIP_CONS *  cons, SCIP_SOL *  sol  )

static

returns whether the given solution is feasible for the given linking constraint

Parameters

scip	SCIP data structure
cons	linking constraint to be checked
sol	primal solution, or NULL for current LP/pseudo solution

Definition at line 1406 of file cons_linking.c.

References NULL, SCIP_Real, SCIPconsGetData(), SCIPconsGetName(), SCIPdebugMessage, SCIPfeastol(), SCIPgetSolVal(), SCIPisFeasEQ(), SCIPisFeasGE(), SCIPisFeasLE(), and SCIPvarIsBinary().

Referenced by enforcePseudo(), SCIP_DECL_CONSCHECK(), and separateCons().

static SCIP_RETCODE createRows ( SCIP *  scip, SCIP_CONS *  cons  )

static

create two rows for the linking constraint

• row1: {sum_{b=1}^n-1 vals[b] * binvars[b]} - intvar = 0
• row2: {sum_{b=0}^n-1 binvars[b]} = 1.0

Parameters

scip	SCIP data structure
cons	linking constraint

Definition at line 1563 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_MAXSTRLEN, SCIP_OKAY, SCIP_Real, SCIPaddVarsToRowSameCoef(), SCIPaddVarToRow(), SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconsGetName(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsRemovable(), SCIPcreateEmptyRowCons(), and SCIPsnprintf().

Referenced by addCuts().

static SCIP_RETCODE addCuts ( SCIP *  scip, SCIP_CONS *  cons, SCIP_SOL *  sol, SCIP_Bool *  cutoff  )

static

adds linking constraint as cut to the LP

Parameters

scip	SCIP data structure
cons	linking constraint
sol	primal CIP solution, NULL for current LP solution
cutoff	whether a cutoff has been detected

Definition at line 1613 of file cons_linking.c.

References createRows(), FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPaddCut(), SCIPconsGetData(), SCIPconsGetName(), SCIPdebugMessage, SCIProwIsInLP(), and TRUE.

Referenced by SCIP_DECL_CONSINITLP(), and separateCons().

static SCIP_RETCODE separateCons ( SCIP *  scip, SCIP_CONS *  cons, SCIP_SOL *  sol, SCIP_Bool *  cutoff, SCIP_Bool *  separated, int *  nchgbds  )

static

checks constraint for violation, and adds it as a cuts if possible

Parameters

scip	SCIP data structure
cons	linking constraint to be separated
sol	primal CIP solution, NULL for current LP solution
cutoff	pointer to store TRUE, if the node can be cut off
separated	pointer to store TRUE, if a cut was found
nchgbds	pointer to store the number of changed variables bounds

Definition at line 1661 of file cons_linking.c.

References addCuts(), checkCons(), CONSHDLR_NAME, FALSE, MIN, NULL, processIntegerBoundChg(), SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconsGetName(), SCIPconshdlrGetName(), SCIPdebugMessage, SCIPgetRowLPFeasibility(), SCIPincConsAge(), SCIPisFeasNegative(), SCIPresetConsAge(), SCIProwIsInLP(), and TRUE.

Referenced by SCIP_DECL_CONSENFOLP(), SCIP_DECL_CONSSEPALP(), and SCIP_DECL_CONSSEPASOL().

static SCIP_RETCODE enforcePseudo ( SCIP *  scip, SCIP_CONS *  cons, SCIP_Bool *  cutoff, SCIP_Bool *  infeasible, int *  nchgbds, SCIP_Bool *  solvelp  )

static

enforces the pseudo solution on the given constraint

Parameters

scip	SCIP data structure
cons	linking constraint to be separated
cutoff	pointer to store TRUE, if the node can be cut off
infeasible	pointer to store TRUE, if the constraint was infeasible
nchgbds	pointer to store the number of changed variable bounds
solvelp	pointer to store TRUE, if the LP has to be solved

Definition at line 1755 of file cons_linking.c.

References checkCons(), CONSHDLR_NAME, FALSE, NULL, processBinvarFixings(), processIntegerBoundChg(), SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIPconsGetHdlr(), SCIPconshdlrGetName(), SCIPhasCurrentNodeLP(), SCIPincConsAge(), SCIPresetConsAge(), and TRUE.

Referenced by SCIP_DECL_CONSENFOPS().

static SCIP_DECL_CONSHDLRCOPY ( conshdlrCopyLinking  )

static

copy method for constraint handler plugins (called when SCIP copies plugins)

Definition at line 1818 of file cons_linking.c.

References CONSHDLR_NAME, NULL, SCIP_CALL, SCIP_OKAY, SCIPconshdlrGetName(), SCIPincludeConshdlrLinking(), and TRUE.

static SCIP_DECL_CONSFREE ( consFreeLinking  )

static

destructor of constraint handler to free constraint handler data (called when SCIP is exiting)

Definition at line 1834 of file cons_linking.c.

References CONSHDLR_NAME, conshdlrdataFree(), NULL, SCIP_CALL, SCIP_OKAY, SCIPconshdlrGetData(), and SCIPconshdlrGetName().

static SCIP_DECL_CONSINITPRE ( consInitpreLinking  )

static

presolving initialization method of constraint handler (called when presolving is about to begin)

Definition at line 1854 of file cons_linking.c.

References consdataLinearize(), NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), SCIPconshdlrGetData(), SCIPconsIsAdded(), SCIPdelCons(), SCIPdisableCons(), and SCIPvarGetLbGlobal().

static SCIP_DECL_CONSEXITSOL ( consExitsolLinking  )

static

solving process deinitialization method of constraint handler (called before branch and bound process data is freed)

Definition at line 1891 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), and SCIPreleaseRow().

static SCIP_DECL_CONSDELETE ( consDeleteLinking  )

static

frees specific constraint data

Definition at line 1917 of file cons_linking.c.

References consdataFree(), CONSHDLR_NAME, dropAllEvents(), getHashmapKey(), NULL, SCIP_CALL, SCIP_OKAY, SCIPconshdlrGetData(), SCIPconshdlrGetName(), SCIPhashmapExists(), SCIPhashmapRemove(), and SCIPisTransformed().

static SCIP_DECL_CONSTRANS ( consTransLinking  )

static

transforms constraint data into data belonging to the transformed problem

Definition at line 1949 of file cons_linking.c.

References consdataCreate(), CONSHDLR_NAME, getHashmapKey(), NULL, SCIP_CALL, SCIP_OKAY, SCIP_STAGE_TRANSFORMING, SCIPconsGetData(), SCIPconsGetName(), SCIPconshdlrGetData(), SCIPconshdlrGetName(), SCIPconsIsChecked(), SCIPconsIsDynamic(), SCIPconsIsEnforced(), SCIPconsIsInitial(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsPropagated(), SCIPconsIsRemovable(), SCIPconsIsSeparated(), SCIPconsIsStickingAtNode(), SCIPcreateCons(), SCIPdebugMessage, SCIPgetStage(), SCIPhashmapInsert(), and SCIPvarGetName().

static SCIP_DECL_CONSINITLP ( consInitlpLinking  )

static

LP initialization method of constraint handler (called before the initial LP relaxation at a node is solved)

Definition at line 1993 of file cons_linking.c.

References addCuts(), NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), and SCIPconsIsInitial().

static SCIP_DECL_CONSSEPALP ( consSepalpLinking  )

static

separation method of constraint handler for LP solutions

Definition at line 2019 of file cons_linking.c.

References CONSHDLR_NAME, FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTFIND, SCIP_OKAY, SCIP_REDUCEDDOM, SCIP_SEPARATED, SCIPconshdlrGetName(), SCIPdebugMessage, and separateCons().

static SCIP_DECL_CONSSEPASOL ( consSepasolLinking  )

static

separation method of constraint handler for arbitrary primal solutions

Definition at line 2059 of file cons_linking.c.

References CONSHDLR_NAME, FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTFIND, SCIP_OKAY, SCIP_REDUCEDDOM, SCIP_SEPARATED, SCIPconshdlrGetName(), SCIPdebugMessage, and separateCons().

static SCIP_DECL_CONSENFOLP ( consEnfolpLinking  )

static

constraint enforcing method of constraint handler for LP solutions

Definition at line 2099 of file cons_linking.c.

References CONSHDLR_NAME, FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_FEASIBLE, SCIP_OKAY, SCIP_REDUCEDDOM, SCIP_SEPARATED, SCIPconshdlrGetName(), SCIPdebugMessage, and separateCons().

static SCIP_DECL_CONSENFOPS ( consEnfopsLinking  )

static

constraint enforcing method of constraint handler for pseudo solutions

Definition at line 2145 of file cons_linking.c.

References CONSHDLR_NAME, enforcePseudo(), FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTRUN, SCIP_FEASIBLE, SCIP_INFEASIBLE, SCIP_OKAY, SCIP_REDUCEDDOM, SCIP_SOLVELP, SCIPconshdlrGetName(), and SCIPdebugMessage.

static SCIP_DECL_CONSCHECK ( consCheckLinking  )

static

feasibility check method of constraint handler for integral solutions

Definition at line 2194 of file cons_linking.c.

References checkCons(), CONSHDLR_NAME, NULL, SCIP_CALL, SCIP_FEASIBLE, SCIP_INFEASIBLE, SCIP_OKAY, SCIP_Real, SCIPconsGetData(), SCIPconshdlrGetName(), SCIPgetSolVal(), SCIPinfoMessage(), SCIPisFeasEQ(), SCIPisFeasIntegral(), SCIPprintCons(), SCIProwIsInLP(), SCIPvarGetName(), and SCIPvarIsBinary().

static SCIP_DECL_CONSPROP ( consPropLinking  )

static

domain propagation method of constraint handler

Definition at line 2280 of file cons_linking.c.

References CONSHDLR_NAME, FALSE, NULL, processBinvarFixings(), processIntegerBoundChg(), SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTFIND, SCIP_OKAY, SCIP_REDUCEDDOM, SCIPconshdlrGetName(), SCIPdebugMessage, and TRUE.

static SCIP_DECL_CONSPRESOL ( consPresolLinking  )

static

presolving method of constraint handler

Definition at line 2321 of file cons_linking.c.

References aggregateVariables(), CONSHDLR_NAME, FALSE, NULL, processIntegerBoundChg(), removeFixedBinvars(), SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTFIND, SCIP_OKAY, SCIP_Real, SCIP_SUCCESS, SCIPaddClique(), SCIPaggregateVars(), SCIPconsGetData(), SCIPconsGetName(), SCIPconshdlrGetData(), SCIPconshdlrGetName(), SCIPconsIsActive(), SCIPconsIsEnabled(), SCIPconsIsModifiable(), SCIPdebugMessage, SCIPdelCons(), SCIPfixVar(), SCIPisStopped(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetUbGlobal(), tightenedIntvar(), and TRUE.

static SCIP_DECL_CONSRESPROP ( consRespropLinking  )

static

propagation conflict resolving method of constraint handler

Definition at line 2651 of file cons_linking.c.

References CONSHDLR_NAME, FALSE, NULL, SCIP_BOUNDTYPE_LOWER, SCIP_BOUNDTYPE_UPPER, SCIP_CALL, SCIP_DIDNOTFIND, SCIP_OKAY, SCIP_SUCCESS, SCIPaddConflictBinvar(), SCIPaddConflictLb(), SCIPaddConflictUb(), SCIPconsGetData(), SCIPdebugMessage, SCIPisFeasEQ(), SCIPvarGetLbAtIndex(), SCIPvarGetUbAtIndex(), SCIPvarGetUbLocal(), SCIPvarIsBinary(), and TRUE.

static SCIP_DECL_CONSLOCK ( consLockLinking  )

static

variable rounding lock method of constraint handler

Definition at line 2827 of file cons_linking.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPaddVarLocks(), and SCIPconsGetData().

static SCIP_DECL_CONSENABLE ( consEnableLinking  )

static

constraint enabling notification method of constraint handler

Definition at line 2849 of file cons_linking.c.

References consdataLinearize(), NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), SCIPconshdlrGetData(), SCIPdelCons(), SCIPdisableCons(), and SCIPvarGetLbGlobal().

static SCIP_DECL_CONSPRINT ( consPrintLinking  )

static

constraint display method of constraint handler

Definition at line 2877 of file cons_linking.c.

References consdataPrint(), NULL, SCIP_CALL, SCIP_OKAY, and SCIPconsGetData().

static SCIP_DECL_CONSCOPY ( consCopyLinking  )

static

constraint copying method of constraint handler

Definition at line 2891 of file cons_linking.c.

References CONSHDLR_NAME, NULL, SCIP_CALL, SCIP_INVALIDDATA, SCIP_OKAY, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconsGetName(), SCIPconshdlrGetName(), SCIPcreateConsLinking(), SCIPduplicateBufferArray, SCIPerrorMessage, SCIPfreeBufferArrayNull, SCIPgetVarCopy(), and TRUE.

static SCIP_DECL_CONSPARSE ( consParseLinking  )

static

constraint parsing method of constraint handler

Definition at line 2968 of file cons_linking.c.

References FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_VERBLEVEL_MINIMAL, SCIPallocBufferArray, SCIPcreateConsLinking(), SCIPfreeBufferArray, SCIPisIntegral(), SCIPparseVarName(), SCIPparseVarsLinearsum(), SCIPreallocBufferArray, SCIPverbMessage(), and TRUE.

static SCIP_DECL_CONSGETVARS ( consGetVarsLinking  )

static

constraint method of constraint handler which returns the variables (if possible)

Definition at line 3071 of file cons_linking.c.

References BMScopyMemoryArray, FALSE, NULL, SCIP_OKAY, SCIPconsGetData(), and TRUE.

static SCIP_DECL_CONSGETNVARS ( consGetNVarsLinking  )

static

constraint method of constraint handler which returns the number of variables (if possible)

Definition at line 3094 of file cons_linking.c.

References NULL, SCIP_OKAY, SCIPconsGetData(), and TRUE.

static SCIP_DECL_EVENTEXEC ( eventExecBinvar  )

static

execution method of event handler

Definition at line 3113 of file cons_linking.c.

References EVENTHDLR_NAME, NULL, SCIP_EVENTTYPE_LBRELAXED, SCIP_EVENTTYPE_LBTIGHTENED, SCIP_EVENTTYPE_UBRELAXED, SCIP_EVENTTYPE_UBTIGHTENED, SCIP_INVALIDDATA, SCIP_OKAY, SCIPerrorMessage, SCIPeventGetType(), and SCIPeventhdlrGetName().

SCIP_RETCODE SCIPincludeConshdlrLinking

(

SCIP *

scip

)

creates the handler for linking constraints and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 3163 of file cons_linking.c.

References CONSHDLR_CHECKPRIORITY, CONSHDLR_DELAYPRESOL, CONSHDLR_DELAYPROP, CONSHDLR_DELAYSEPA, CONSHDLR_DESC, CONSHDLR_EAGERFREQ, CONSHDLR_ENFOPRIORITY, CONSHDLR_MAXPREROUNDS, CONSHDLR_NAME, CONSHDLR_NEEDSCONS, CONSHDLR_PROP_TIMING, CONSHDLR_PROPFREQ, CONSHDLR_SEPAFREQ, CONSHDLR_SEPAPRIORITY, conshdlrdataCreate(), DEFAULT_LINEARIZE, EVENTHDLR_DESC, EVENTHDLR_NAME, FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPaddBoolParam(), SCIPincludeConshdlrBasic(), SCIPincludeEventhdlrBasic(), SCIPsetConshdlrCopy(), SCIPsetConshdlrDelete(), SCIPsetConshdlrEnable(), SCIPsetConshdlrExitsol(), SCIPsetConshdlrFree(), SCIPsetConshdlrGetNVars(), SCIPsetConshdlrGetVars(), SCIPsetConshdlrInitlp(), SCIPsetConshdlrInitpre(), SCIPsetConshdlrParse(), SCIPsetConshdlrPresol(), SCIPsetConshdlrPrint(), SCIPsetConshdlrProp(), SCIPsetConshdlrResprop(), SCIPsetConshdlrSepa(), and SCIPsetConshdlrTrans().

Referenced by SCIP_DECL_CONSHDLRCOPY(), and SCIPincludeDefaultPlugins().

SCIP_RETCODE SCIPcreateConsLinking	(	SCIP *	scip,
		SCIP_CONS **	cons,
		const char *	name,
		SCIP_VAR *	intvar,
		SCIP_VAR **	binvars,
		int *	vals,
		int	nbinvars,
		SCIP_Bool	initial,
		SCIP_Bool	separate,
		SCIP_Bool	enforce,
		SCIP_Bool	check,
		SCIP_Bool	propagate,
		SCIP_Bool	local,
		SCIP_Bool	modifiable,
		SCIP_Bool	dynamic,
		SCIP_Bool	removable,
		SCIP_Bool	stickingatnode
	)

creates and captures a linking constraint

Note

the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()

Parameters

scip	SCIP data structure
cons	pointer to hold the created constraint
name	name of constraint
intvar	integer variable which should be linked
binvars	binary variables, or NULL
vals	coefficients of the binary variables
nbinvars	number of binary variables
initial	should the LP relaxation of constraint be in the initial LP? Usually set to TRUE. Set to FALSE for 'lazy constraints'.
separate	should the constraint be separated during LP processing? Usually set to TRUE.
enforce	should the constraint be enforced during node processing? TRUE for model constraints, FALSE for additional, redundant constraints.
check	should the constraint be checked for feasibility? TRUE for model constraints, FALSE for additional, redundant constraints.
propagate	should the constraint be propagated during node processing? Usually set to TRUE.
local	is constraint only valid locally? Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints.
modifiable	is constraint modifiable (subject to column generation)? Usually set to FALSE. In column generation applications, set to TRUE if pricing adds coefficients to this constraint.
dynamic	is constraint subject to aging? Usually set to FALSE. Set to TRUE for own cuts which are separated as constraints.
removable	should the relaxation be removed from the LP due to aging or cleanup? Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'.
stickingatnode	should the constraint always be kept at the node where it was added, even if it may be moved to a more global node? Usually set to FALSE. Set to TRUE to for constraints that represent node data.

Definition at line 3222 of file cons_linking.c.

References consdataCreate(), CONSHDLR_NAME, getHashmapKey(), HASHSIZE_BINVARSCONS, NULL, SCIP_CALL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPblkmem(), SCIPconshdlrGetData(), SCIPcreateCons(), SCIPdebugMessage, SCIPerrorMessage, SCIPfindConshdlr(), SCIPgetStage(), SCIPhashmapCreate(), SCIPhashmapExists(), SCIPhashmapInsert(), SCIPisInfinity(), SCIPvarGetLbGlobal(), SCIPvarGetName(), and SCIPvarGetUbGlobal().

Referenced by consdataCollectLinkingCons(), SCIP_DECL_CONSCOPY(), SCIP_DECL_CONSPARSE(), and SCIPcreateConsBasicLinking().

SCIP_RETCODE SCIPcreateConsBasicLinking	(	SCIP *	scip,
		SCIP_CONS **	cons,
		const char *	name,
		SCIP_VAR *	intvar,
		SCIP_VAR **	binvars,
		int *	vals,
		int	nbinvars
	)

creates and captures a linking constraint in its most basic version, i. e., all constraint flags are set to their basic value as explained for the method SCIPcreateConsLinking(); all flags can be set via SCIPsetCons<Flagname>-methods in scip.h

See Also

SCIPcreateConsLinking() for information about the basic constraint flag configuration

Note

the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()

Parameters

scip	SCIP data structure
cons	pointer to hold the created constraint
name	name of constraint
intvar	integer variable which should be linked
binvars	binary variables, or NULL
vals	coefficients of the binary variables
nbinvars	number of binary variables

Definition at line 3308 of file cons_linking.c.

References FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPcreateConsLinking(), and TRUE.

SCIP_Bool SCIPexistsConsLinking	(	SCIP *	scip,
		SCIP_VAR *	intvar
	)

checks if for the given integer variable a linking constraint exists

Parameters

scip	SCIP data structure
intvar	integer variable which should be linked

Definition at line 3327 of file cons_linking.c.

References CONSHDLR_NAME, getHashmapKey(), NULL, SCIPconshdlrGetData(), SCIPfindConshdlr(), and SCIPhashmapExists().

Referenced by collectBinaryVars(), and consdataCollectLinkingCons().

SCIP_CONS* SCIPgetConsLinking	(	SCIP *	scip,
		SCIP_VAR *	intvar
	)

returns the linking constraint belonging to the given integer variable or NULL if it does not exist yet

Parameters

scip	SCIP data structure
intvar	integer variable which should be linked

Definition at line 3345 of file cons_linking.c.

References CONSHDLR_NAME, getHashmapKey(), NULL, SCIPconshdlrGetData(), SCIPfindConshdlr(), and SCIPhashmapGetImage().

Referenced by collectBinaryVars(), consdataCollectLinkingCons(), and consdataCreate().

SCIP_VAR* SCIPgetIntvarLinking	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

returns the integer variable of the linking constraint

Parameters

scip	SCIP data structure
cons	linking constraint

Definition at line 3366 of file cons_linking.c.

References CONSHDLR_NAME, NULL, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

SCIP_RETCODE SCIPgetBinvarsLinking	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_VAR ***	binvars,
		int *	nbinvars
	)

returns the binary variables of the linking constraint

Parameters

scip	SCIP data structure
cons	linking constraint
binvars	pointer to store the binary variables array pointer
nbinvars	pointer to store the number of returned binary variables

Definition at line 3388 of file cons_linking.c.

References consdataCreateBinvars(), CONSHDLR_NAME, NULL, SCIP_CALL, SCIP_INVALIDDATA, SCIP_OKAY, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetData(), SCIPconshdlrGetName(), and SCIPerrorMessage.

Referenced by collectBinaryVars(), and createCoverCutsTimepoint().

int SCIPgetNBinvarsLinking	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

returns the number of binary variables of the linking constraint

Parameters

scip	SCIP data structure
cons	linking constraint

Definition at line 3432 of file cons_linking.c.

References CONSHDLR_NAME, NULL, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

int* SCIPgetValsLinking	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

returns the coefficients of the binary variables

Parameters

scip	SCIP data structure
cons	linking constraint

Definition at line 3453 of file cons_linking.c.

References CONSHDLR_NAME, NULL, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

Referenced by collectBinaryVars(), and createCoverCutsTimepoint().